Changeset 59817 in webkit for trunk/JavaScriptCore/bytecompiler/BytecodeGenerator.cpp

Timestamp:

May 19, 2010, 9:57:20 PM (15 years ago)

Author:

[email protected]

Message:

Bug 39399 - Move responsibility for verifying constructors return objects from the caller to the callee.

Reviewed by Geoff Garen.

This is a necessary step to move object creation from caller to callee.

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::dump):

• bytecode/Opcode.h:
• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::emitReturn):
(JSC::BytecodeGenerator::emitConstruct):

• bytecompiler/BytecodeGenerator.h:

(JSC::BytecodeGenerator::isConstructor):

• bytecompiler/NodesCodegen.cpp:

(JSC::FunctionBodyNode::emitBytecode):

• interpreter/Interpreter.cpp:

(JSC::Interpreter::privateExecute):

• jit/JIT.cpp:

(JSC::JIT::privateCompileMainPass):
(JSC::JIT::privateCompileSlowCases):

• jit/JIT.h:
• jit/JITCall.cpp:

(JSC::JIT::emit_op_constructor_ret):

• jit/JITOpcodes.cpp:

(JSC::JIT::emit_op_constructor_ret):

File:

• trunk/JavaScriptCore/bytecompiler/BytecodeGenerator.cpp (modified) (3 diffs)

trunk/JavaScriptCore/bytecompiler/BytecodeGenerator.cpp

@@ -366 +366 @@
     ++m_codeBlock->m_numParameters;
 
-    if (functionBody->usesThis() || m_shouldEmitDebugHooks) {
+    if (!isConstructor() && (functionBody->usesThis() || m_shouldEmitDebugHooks)) {
         emitOpcode(op_convert_this);
         instructions().append(m_thisRegister.index());
@@ -1542 +1542 @@
     }
 
+    // Constructors use op_constructor_ret to check the result is an
+    // object, unless we can trivially determine the check is not
+    // necessary (currently, if the return value is 'this').
+    if (isConstructor() && (src->index() != m_thisRegister.index())) {
+        emitOpcode(op_constructor_ret);
+        instructions().append(src->index());
+        instructions().append(m_thisRegister.index());
+        return src;
+    }
     return emitUnaryNoDstOp(op_ret, src);
 }
@@ -1607 +1616 @@
     instructions().append(funcProto->index()); // proto
     instructions().append(argv[0]->index()); // thisRegister
-
-    emitOpcode(op_construct_verify);
-    instructions().append(dst->index());
-    instructions().append(argv[0]->index());
 
     if (m_shouldEmitProfileHooks) {